I have dietpi running on RPI 3B+ , working smoothly for few months, software installed is Kodi , Transmission and MariaDB which i use to remotely connect to from another RPI.

Database is around 200mb and i have moves User Data to USB stick plugged to RPI.
Yesterday i tried to do backup and after its finished i couldn't start MariaDB anymore.

Is there a simpler way to fix or i need to start from scratch? I wouldn't want to loose months of data in the database.

here's part of the log

2019-08-06 19:17:06 1988513584 [Note] InnoDB: innodb_empty_free_list_algorithm has been changed to legacy because of small buffer pool size. In order to use backoff, increase buffer pool at least up to 20MB.